Firefighters were called the cobblestone Alley between Main and Dwight Streets around 11:40 AM because a manhole cover blew off.

Fire department spokesman Dennis Leger told 22News if wires begin to smolder they can give off “unburned products of combustion” which can build up and ignite; that’s what caused the manhole cover to blow off.

Eversource crews are now checking those wires. Firefighters are there as backup to make sure none of the other wiring to nearby buildings becomes affected. No buildings have been evacuated.